Phoneutria nigriventer toxins block tityustoxin-induced calcium influx in synaptosomes.

نویسندگان

  • D M Miranda
  • M A Romano-Silva
  • E Kalapothakis
  • C R Diniz
  • M N Cordeiro
  • T M Santos
  • M A Prado
  • M V Gomez
چکیده

Neurotoxins can help the understanding of mechanisms involved in neurotransmission. We here report that two neurotoxin isoforms, Tx3-3 and Tx3-4 obtained from the venom of the spider Phoneutria nigriventer inhibited the 45Ca2+ influx in rat cortical synaptosomes induced by the scorpion venom tityustoxin. The IC50 for Tx3-3 and Tx3-4 were 0.32 and 7.9 nM, respectively. The neurotoxins Tx3-3 and Tx3-4 are very effective in inhibiting 45Ca2+ influx and they should be useful in studies involving Ca(2+)-dependent processes.

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عنوان ژورنال:
  • Neuroreport

دوره 9 7  شماره 

صفحات  -

تاریخ انتشار 1998